GOETHE'S THEORY OF THE SKULL. 83 
variation, and combination of leaves there arise all the 
varied beauties in form and colour which we admire in the 
green parts, as well as in the organs of propagation, or the 
flowers of plants. Goethe here showed that in order to 
comprehend the whole of the phenomena, we must in the 
first place compare them, and, secondly, search for a simple 
type, a simple fundamental form, of which all other forms 
are only infinite variations. 
Something similar to what he had here done for the meta- 
morphosis of plants he then did for the Vertebrate 
animals, in his celebrated vertebral theory of the skull. 
Goethe was the first to show, independently of Oken, who 
almost simultaneously arrived at the same thought, that the 
skull of man and of all Vertebrate animals, in particular 
mammals, is nothing more than a bony case, formed of 
the same bones,—that is, vertebrae,—out of which the spine 
also is composed. The vertebrz of the skull are like those 
of the spine, bony rings lying behind each other, but in the 
skull are peculiarly changed and specialized (differentiated). 
Although this idea has been strongly modified by recent 
discoveries, yet in Goethe’s day it was one of the greatest 
advances in comparative anatomy, and was not only one 
of the first advances towards the understanding of the 
structure of Vertebrate animals, but at the same time ex- 
plained many individual phenomena. When two parts of a 
body, such as the skull and spine, which appear at first 
sight so different, were proved to be parts originally the 
_ same, developed out of one and the same foundation, one of 
the difficult problems of the philosophy of nature was 
solved. Here again we meet the notion of a single type— 
the conception of a single principle, which becomes in- 
